Apolone, G., Corli, O., Negri, E., Mangano, S., Montanari, M., Greco, M.T., . . . Zucco, F. (2009). Effects of transdermal buprenorphine on patients-reported outcomes in cancer patients: Results from the Cancer Pain Outcome Research (CPOR) Study Group. Clinical Journal of Pain, 25(8), 671–682.

To assess the effects of various analgesic options, particularly transdermal buprenorphine, on cancer-related pain

This study is a multicenter trial in which participants were patients with advanced solid tumors and persistent cancer-related pain that required analgesic treatment. For one month investigators collected descriptive data, including data from screening and weekly assessments and data related to medical history, examination findings, medications, analgesic consumption, pain assessment, satisfaction with pain treatment, and patient self-reports of quality of life. Data were collected up to the final visit, at week 12. This study did not describe specific pain interventions. Data relating to various subgroups were described and analyzed.

• The sample was composed of 398 patients.
• Mean patient age was 64.4 years.
• Of all patients, 43.9% were female and 56.1% were male.
• The sample comprised a variety of cancer types.
• Of all patients, 64.6% were initially on transdermal buprenorphine at study baseline. During the study the remaining patients switched to buprenorphine from another treatment. Most patients were receiving nonsteroidal anti-inflammatory drugs, and many patients were also taking steroids.
• Of all patients, 42% had concurrent chemotherapy and bone metastasis.
• Worst average pain intensity at baseline was 2.1 among those who initially were receiving buprenorphine. Among those taking a different initial medication, the average pain intensity was 1.6.
• Of all patients, 25.9% had neuropathic pain.

• Multisite
• Multiple outpatient and inpatient settings in Italy

Nonrandomized open-label prospective, descriptive study

• Brief Pain Inventory (five items)
• Eleven-point rating scale, to measure pain
• Seven-point verbal scale, with care scale, to measure satisfaction
• Seven-point numeric rating scale, to measure quality of life
• Four-point verbal rating scale (1 = absent, 4 = very much), to measure side effects

• The most frequent side effects were constipation and sedation. Overall, transdermal buprenorphine was well tolerated.
• When compared to patients using World Health Organization (WHO) level III drugs other than buprenorphine (mean change in overall pain =  –17.7), patients using transdermal buprenorphine (mean change in overall pain = –25.8) had consistently higher levels of improvement in all pain measures and greater levels of pain relief.
• In regard to pain relief, of patients receiving buprenorphine, 19% expressed decreased or worsened satisfaction. Authors determined that approximately 30% of patients could be considered poor responders to buprenorphine.

Patients using transdermal buprenorphine tend to show more pain reduction than patients who are taking other WHO level III analgesia. The majority of patients seem to tolerate transdermal buprenorphine well. Approximately 30% of patients were unresponsive to transdermal buprenorphine.

• The study had a risk of bias due to no appropriate control group.
• Although authors provided much analytic data, they did not present statistical tests of significance of trends over time or cite differences in group outcomes,
• Given the setting of chronic cancer-related pain, observations were made over a relatively short period.

Transdermal buprenorphine may be a helpful alternative and adjunct in the management of cancer-related pain. Note that approximately one-third of patients in the study did not respond to this medication. Other studies have shown that absorption of transdermal medication varies among individuals. Findings point to the importance, in ensuring optimal pain management, of timely and consistent pain reassessment, particularly if switching from one approach to another or when adding medications to a regimen.